/* ZeroHuman Base Template System v1.0 */
/* Mobile-first, high-performance CSS framework */

:root {
  /* Colors */
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-secondary: #64748b;
  --color-accent: #f59e0b;
  --color-success: #10b981;
  --color-error: #ef4444;
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafc;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-border: #e2e8f0;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Sizing */
  --container-max: 1200px;
  --header-height: 64px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

  /* Border radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
}

/* Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, video {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-dark);
}

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
}

h1 { font-size: clamp(1.875rem, 5vw, 2.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }
h4 { font-size: 1.125rem; }

p {
  margin-bottom: var(--space-md);
}

.text-muted {
  color: var(--color-text-muted);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.5rem;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #fff;
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  color: #fff;
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
  background-color: var(--color-primary);
  color: #fff;
}

.btn-accent {
  background-color: var(--color-accent);
  color: #fff;
}

.btn-accent:hover {
  background-color: #d97706;
  color: #fff;
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.0625rem;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.8125rem;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-text);
}

.nav {
  display: none;
}

.nav a {
  color: var(--color-text);
  font-weight: 500;
  padding: var(--space-sm) var(--space-md);
}

.nav a:hover {
  color: var(--color-primary);
}

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-sm);
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: var(--transition-fast);
}

/* Mobile nav */
.nav-open .nav {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: var(--header-height);
  left: 0;
  right: 0;
  background: var(--color-bg);
  padding: var(--space-md);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
}

/* Hero */
.hero {
  padding: var(--space-3xl) 0;
  background: linear-gradient(135deg, var(--color-bg) 0%, var(--color-bg-alt) 100%);
  text-align: center;
}

.hero h1 {
  margin-bottom: var(--space-lg);
}

.hero p {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  max-width: 600px;
  margin: 0 auto var(--space-xl);
}

.hero-cta {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  align-items: center;
}

/* Section */
.section {
  padding: var(--space-3xl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-title p {
  color: var(--color-text-muted);
  max-width: 600px;
  margin: var(--space-sm) auto 0;
}

/* Cards */
.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: box-shadow var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-lg);
}

.card-body {
  padding: var(--space-lg);
}

.card-img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
  background: var(--color-bg-alt);
}

/* Grid */
.grid {
  display: grid;
  gap: var(--space-lg);
}

.grid-2 { grid-template-columns: 1fr; }
.grid-3 { grid-template-columns: 1fr; }
.grid-4 { grid-template-columns: 1fr; }

/* Features */
.feature {
  text-align: center;
  padding: var(--space-lg);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg-alt);
  border-radius: var(--radius-md);
  font-size: 1.5rem;
}

/* Forms */
.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-weight: 500;
  margin-bottom: var(--space-xs);
  font-size: 0.875rem;
}

.form-input {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
  transition: border-color var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

/* Footer */
.footer {
  background: var(--color-text);
  color: #fff;
  padding: var(--space-3xl) 0 var(--space-xl);
}

.footer a {
  color: rgba(255, 255, 255, 0.7);
}

.footer a:hover {
  color: #fff;
}

.footer-grid {
  display: grid;
  gap: var(--space-xl);
  margin-bottom: var(--space-2xl);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-xl);
  text-align: center;
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.875rem;
}

/* Utilities */
.text-center { text-align: center; }
.text-left { text-align: left; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.hidden { display: none; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Tablet breakpoint */
@media (min-width: 640px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .hero-cta {
    flex-direction: row;
    justify-content: center;
  }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

/* Desktop breakpoint */
@media (min-width: 1024px) {
  .nav { display: flex; }
  .nav-toggle { display: none; }
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-4 { grid-template-columns: repeat(4, 1fr); }
  .hero { padding: var(--space-3xl) 0 calc(var(--space-3xl) * 1.5); }
  .footer-grid { grid-template-columns: repeat(4, 1fr); }
}

/* Print */
@media print {
  .header, .footer, .btn { display: none; }
  body { font-size: 12pt; }
}